Survival analysis and sentinel lymph node status in thin cutaneous melanoma: A multicenter observational study

• Published in: Cancer medicine (Malden, MA) MA), 2019-08, Vol.8 (9), p.4235-4244
• Main Authors: Tejera‐Vaquerizo, Antonio, Ribero, Simone, Puig, Susana, Boada, Aram, Paradela, Sabela, Moreno‐Ramírez, David, Cañueto, Javier, Unamuno, Blanca, Brinca, Ana, Descalzo‐Gallego, Miguel A., Osella‐Abate, Simona, Cassoni, Paola, Carrera, Cristina, Vidal‐Sicart, Sergi, Bennássar, Antoni, Rull, Ramón, Alos, Llucìa, Requena, Celia, Bolumar, Isidro, Traves, Víctor, Pla, Ángel, Fernández‐Orland, A., Jaka, Ane, Fernández‐Figueres, María T., Hilari, Josep M., Giménez‐Xavier, Pol, Vieira, Ricardo, Botella‐Estrada, Rafael, Román‐Curto, Concepción, Ferrándiz, Lara, Iglesias‐Pena, Nicolás, Ferrándiz, Carlos, Malvehy, Josep, Quaglino, Pietro, Nagore, Eduardo
• Format: Article
• Language: English
• Subjects: Adult; age factors; Aged; Biopsy; Cancer; Clinical Cancer Research; Clinical medicine; Cox proportional hazards regression analysis; Female; Humans; Lymph nodes; Lymphatic Metastasis - diagnosis; Lymphatic Metastasis - pathology; Lymphatic system; Male; Medical prognosis; Melanoma; Melanoma - mortality; Melanoma - pathology; Melanoma, Cutaneous Malignant; Metastases; Metastasis; Middle Aged; Mitosis; mitotic index; multiple imputation; neoplasia staging; Neoplasm Staging; Observational studies; Original Research; Patients; Prognosis; prognostic factors; Sentinel Lymph Node - cytology; Sentinel Lymph Node Biopsy; Skin Neoplasms - mortality; Skin Neoplasms - pathology; Studies; Survival; Survival Analysis; Tumors; Variables
• ISSN: 2045-7634; 2045-7634
• DOI: 10.1002/cam4.2358

Mitotic rate is no longer considered a staging criterion for thin melanoma in the 8th edition of the American Joint Committee on Cancer Staging Manual. The aim of this observational study was to identify prognostic factors for thin melanoma and predictors and prognostic significance of sentinel lymph node (SLN) involvement in a large multicenter cohort of patients with melanoma from nine tertiary care hospitals. A total of 4249 consecutive patients with thin melanoma diagnosed from January 1, 1998 to December 31, 2016 were included. The main outcomes were disease‐free interval and melanoma‐specific survival for the overall population and predictors of SLN metastasis (n = 1083). Associations between survival and SLN status and different clinical and pathologic variables (sex, age, tumor location, mitosis, ulceration, regression, lymphovascular invasion, histologic subtype, Clark level, and Breslow thickness) were analyzed by Cox proportional hazards regression and logistic regression. SLN status was the most important prognostic factor for melanoma‐specific survival (hazard ratio, 13.8; 95% CI, 6.1‐31.2; P 2 mitoses/mm2 was the only factor associated with a positive SLN biopsy (odds ratio, 2.9; 95% CI, 1.22‐7; P = 0.01. SLN status is the most important prognostic factor in thin melanoma. A high mitotic rate is associated with metastatic SLN involvement. SLN biopsy should be discussed and recommended in patients with thin melanoma and a high mitotic rate. The mitotic rate is no longer considered a staging criterion by 8th staging system. The mitotic rate is not associated with the prognosis of patients with thin melanoma but is associated with a positive SLN. The presence of >2 mitoses/mm in T1a melanomas recommends discussing the sentinel lymph node biopsy.